1994 c2500 no second gear

[Jjbiskup]

Hey i just got a 1994 c2500 with a 4.3 and 4l80e trans with 77k miles for free. Guy said it had no fluid on the dipstick. I put about 2 quarts of valvoline dex/merc in it(i know it should optimally be dexron VI but its what i had laying around) So driving it, truck does not shift into 2nd 70% of the time, feels like a neutral until you floor it. I may have overfilled the trans. Would this be a reason as to why theres no 2nd? Also first time I checked it i believe there might have been a little bit of water on the dipstick.

 

[NickTransmissions]

Would this be a reason as to why theres no 2nd?

No. smoked intermediate clutch, failing intermediate one way clutch assembly or both is likely the cause. Another possibility is a massive leak at the 1-2 accumulator piston due to worn sealing rings/orings on the piston or worn inner diameter of the low reverse piston where the 1-2 acc piston is located.

Drop the pan asap to confirm or deny the presence of water contamination. If you have coolant leaking into the trans, it needs to be pulled and torn down immediately. Coolant contamination usually translates to a total loss of the unit. Heavier water displaces lighter fluid and gear train parts are meshing together without any lubrication, etc....

 

[Jjbiskup]

No. smoked intermediate clutch, failing intermediate one way clutch assembly or both is likely the cause. Another possibility is a massive leak at the 1-2 accumulator piston due to worn sealing rings/orings on the piston or worn inner diameter of the low reverse piston where the 1-2 acc piston is located.

Drop the pan asap to confirm or deny the presence of water contamination. If you have coolant leaking into the trans, it needs to be pulled and torn down immediately. Coolant contamination usually translates to a total loss of the unit. Heavier water displaces lighter fluid and gear train parts are meshing together without any lubrication, etc....

Im not 100% sure of water. So there is no possibility that the 4l80e overfilled by a quart or so will cause it to not engage into second? Like i said it will engage when full throttled sometimes. Also would it be possible to rebuild a 4l80e with no transmission experience at home? And how much would it cost.

 

[NickTransmissions]

Im not 100% sure of water. So there is no possibility that the 4l80e overfilled by a quart or so will cause it to not engage into second? Like i said it will engage when full throttled sometimes. Also would it be possible to rebuild a 4l80e with no transmission experience at home? And how much would it cost.

No to your first question. And to your second question: yes, it's very possible!

Check out my 4L80E playlist on youtube for parts selection considerations and reassembly procedures. I should also have a teardown and inspection video on there early next week as well which will walk viewers through what to inspect/check for and how to do it. Additionally i should have a 4L80E information thread posted by then also.

Costs will run you about $900-$1100 or so, maybe a little more or a little less, assuming you replace everything you should be replacing (my 4L80E info thread will have a complete list of parts when it's posted).